You can control the time and days a computer can access your AirPort Extreme network. You can determine when a user can use the network to access the Internet, share files, or play games.
Open AirPort Utility, located in the Utilities folder in the Applications folder on a Mac, and in Start > All Programs > AirPort on a Windows computer.
Select your base station or your Time Capsule, and then click Manual Setup. Enter the password if necessary.
Click AirPort in the toolbar, and then click Access Control.
Click the Add (+) button and enter the MAC address and description or name of the computers you’re allowing to access the network. You can also click This Computer to add the MAC address and name of the computer you’re using.
Choose a value from the pop-up menus. Choose a day of the week or everyday from the day pop-up menu, and then choose either "all day" or "between" from the other pop-up menu. If you choose "between," you can edit the times of the day by double-clicking in the time fields.
If there are no computers listed, you can adjust the default behavior for any user joining the network by clicking Edit and choosing values from the pop-up menus.